TY - JOUR

T1 - Photolysis of sulfamethoxypyridazine in various aqueous media

T2 - Aerobic biodegradation and identification of photoproducts by LC-UV-MS/MS

AU - Khaleel, Nareman D H

AU - Mahmoud, Waleed M M

AU - Hadad, Ghada M

AU - Abdel-Salam, Randa A

AU - Kümmerer, Klaus

N1 - Copyright © 2012 Elsevier B.V. All rights reserved.

PY - 2013/1/15

Y1 - 2013/1/15

N2 - Sulfonamides are one of the most frequently used antibiotics worldwide. Therefore, mitigation processes such as abiotic or biotic degradation are of interest. Photodegradation and biodegradation are the potentially significant removal mechanisms for pharmaceuticals in aquatic environments. The photolysis of sulfamethoxypyridazine (SMP) using a medium pressure Hg-lamp was evaluated in three different media: Millipore water pH 6.1 (MW), effluent from sewage treatment plant pH 7.6 (STP), and buffered demineralized water pH 7.4 (BDW). Identification of transformation products (TPs) was performed by LC-UV-MS/MS. The biodegradation of SMP using two tests from the OECD series was studied: Closed Bottle test (OECD 301 D), and Manometric Respirometry test (OECD 301 F). In biodegradation tests, it was found that SMP was not readily biodegradable so it may pose a risk to the environment. The results showed that SMP was removed completely within 128. min of irradiation in the three media, and the degradation rate was different for each investigated type of water. However, dissolved organic carbon (DOC) was not removed in BDW and only little DOC removal was observed in MW and STP, thus indicating the formation of TPs. Analysis by LC-UV-MS/MS revealed new TPs formed. The hydroxylation of SMP represents the main photodegradation pathway.

AB - Sulfonamides are one of the most frequently used antibiotics worldwide. Therefore, mitigation processes such as abiotic or biotic degradation are of interest. Photodegradation and biodegradation are the potentially significant removal mechanisms for pharmaceuticals in aquatic environments. The photolysis of sulfamethoxypyridazine (SMP) using a medium pressure Hg-lamp was evaluated in three different media: Millipore water pH 6.1 (MW), effluent from sewage treatment plant pH 7.6 (STP), and buffered demineralized water pH 7.4 (BDW). Identification of transformation products (TPs) was performed by LC-UV-MS/MS. The biodegradation of SMP using two tests from the OECD series was studied: Closed Bottle test (OECD 301 D), and Manometric Respirometry test (OECD 301 F). In biodegradation tests, it was found that SMP was not readily biodegradable so it may pose a risk to the environment. The results showed that SMP was removed completely within 128. min of irradiation in the three media, and the degradation rate was different for each investigated type of water. However, dissolved organic carbon (DOC) was not removed in BDW and only little DOC removal was observed in MW and STP, thus indicating the formation of TPs. Analysis by LC-UV-MS/MS revealed new TPs formed. The hydroxylation of SMP represents the main photodegradation pathway.

KW - Chemistry

KW - Aquatic environment

KW - Biodegradation

KW - Photodegradation

KW - Sulfonamides

KW - Transformation products

UR - http://www.scopus.com/inward/record.url?scp=84872605597&partnerID=8YFLogxK

U2 - 10.1016/j.jhazmat.2012.10.059

DO - 10.1016/j.jhazmat.2012.10.059

M3 - Journal articles

C2 - 23183348

VL - 244-245

SP - 654

EP - 661

JO - Journal of Hazardous Materials

JF - Journal of Hazardous Materials

SN - 0304-3894

ER -